Internally applied expanding friction-grip wrench



Oct. 30, 1951 R. R. GossARD INTERNALLY APPLIED, EXPANDING FRICTION-GRIPWRENCH b Filed Sept. 9, 1946 mmm INVENToR. ay, 'osarfl Patented Oct. 30,1951 INTERNALLY APPLIED EXPANDING FRICTION-GRIP WRENCH Roy R. Gossard,Glendora, Calif.

Application September 9, 1946,Serial No. 695,736

4 Claims.

rI`his invention relates to an inside wrench for enabling a piece ofpipe, or a pipe-fitter, to be rotated on i'ts axis. The wrench embodyingthis invention is particularly useful to attach or detach a pipe-fittingor section of pipe in a situation where the part to be removed projectsonly a short distance from a wall that would be likely to be injured ormarred by the application of an ordinary outside wrench to the tting.And it is also particularly useful in a situation where a wrench appliedto the outside of a pipe connection, would have to be applied onexternal threads likely to become flattened down or marred by thepressure of the wrench upon the same.

One of the objects of the invention is to provide a tool of thischaracter, of few parts and simple construction, that can be readilyapplied and operated for the purpose stated.

Another object of the invention is to provide a tool of this type, whichwill operate as readily for rotation in one direction as in the other,thereby enabling torque to be applied in either direction, for fittingshaving a right-hand or a left-hand thread. l

Another object of the invention is to provide i a tool of thischaracter, which includes in its construction two jaws and a rotarymember or mandrel between the same; and to provide such a tool withmeans for retaining the jaws and operating in such a way as to permit alimited but suicient expanding movement of the jaws without thenecessity of providing a cage or similar means for retaining the jaws.

Further objects of the invention will appear hereinafter.

The invention consists in the novel parts and combinations of parts tobe described hereinafter,

all of which contribute to produce an eicient two-way inside wrench.

A preferred embodiment of the invention is described in the followingspecification, while the broad scope of the invention is pointed out inthe appended claims.

In the drawing;

Fig. l is a Vertical section taken through a portion of a wall andshowing the end portion oi a pipe end or pipe ntting projecting from thesame, and also illustrating this wrench partially in elevation, andpartially in section taken about on the line l-I of Fig. 3.

Fig. 2 is a side elevation of the tool, illustrating the same removedfrom the `pipe tting illustrated in Fig. 1.

Fig. 3 is a vertical section taken on the line 3 3 of Fig. 2 looking inthe direction of the arrow,

showing the jaws -of the tool in a neutral or unapplied position; andalso showing in cross-section, the wall of a pipetting within which thewrench may be used. This-view is upon a larger scale than Fig. 2.

Fig. 4 is a view similar to Fig. 3, and upon the same scale, but showingthe jaws expanded by the mandrel into their clamping position.

Fig. 5 is a side view of a retaining link which constitutes a feature ofthe invention, and which is employed as a shackle or link to cooperatewith other parts in retaining the jaws on the mandrel.

In practicing this invention, I provide an arbor or mandrel I, on whichI provide means for expanding the jaws of the wrench. The form of thismeans will depend upon how many jaws the wrench is provided with. Whileof course there may be as many of these jaws as desired, `in the presentinstance I prefer to employ only two jaws 2 and 3, and in that case theexpanding means preferably consists of cam means including twodiametrically opposite extensions or cam toes 4 that are lformed atdiametrically opposite points on the mandrel. At the point where thesecam toes are located, the mandrel may have an ellip.- ticalcross-section to :form the cam body V5, and on each side ofvthis cam`body the mandrel has two cylindrical necks 6 and` l. In otherwords, themandrel would ordinarily be made out of round iron or steel, and would.be formed `up at about its middle .point to produce theV cam body 5;and beyond one Vof the necksfor .example, the neck 1, Van angular shank8 may be formed to receive ran `angular `or square ,socket Wrench to`enable the mandrel to .be rotated to expand its jaws, and Aturn .the4pipe iitting.

In the present instance, the two jaws 2 and 3 have arcuate peripheries9, and they are of substantially semi-circular form, each inner edgebeing formed with a .recess l0 that ts approximately to the profile ofthe `elliptical cam body .5.

The two jaws 2 and 3 are not fastened in any way to the mandrel, but arepreferably freely lioating, and shackled together with a lost-,moa tionshackle connection which prevents their beingdisconnected from themandrel, but which, at the same time, will give them a limited expandingand contracting movement, the former of which will enable them to moveoutwardly suiciently to jam their peripheries against the inner face ofa pipe end or iitting into which the wrench has been introduced.

The. jaws 2 and 3 are of 'relatively thick disc form, and presentatiside :faces Il In order to attain the shackling effect in a simpleand practical manner, I prefer to employ shackles I2.4

These are preferably in the Iorm of short links, the ends of which areprovided with pintles I3 that are adapted to be received in sockets i4formed in the side faces Il or the jaws. In other words, at adjacentpoints the Jaws are provided with oppositely disposed sockets, and inassembling the parts, the pintles I3 are dropped into these sockets sothat the bodies of the links extend across the gap or opening l5between-the inner faces or adjacent edges I6 of the jaws. These pintlesI3 are preferably formed by bending the ends of the links around so thatthe axes of the pintles extend approximately at right angles to thelongitudinal axis of each link. The links are preferably formed of halfround crosssection so that each link presents a flat face I on its outerside, and presents a rounded or half round face I8 on its inner side,that is to say, on the side that is disposed toward the jaws. In orderto provide clearance for the bodies of these links, each jaw is providedwith a clearance slot I9, the sides of which diverge toward the gap l5between the jaws. These clearance slots give clearance and permitfreedom of movement of the links when the jaws are shifted outwardly tojam their outer faces against the inner face of the wall of the fitting.The links are retained in connection with the jaws, preferably by meansof loose washers 20 which are of'relatively thin flat metal, and thesewashers are held in position or backed up by followers, or substantialcollars 2 l, which iit over the cylindrical necks 6 and 1, and which aresecured to the said necks by any suitable means such as set screws 22.These set screws are preferably countersunk into the bodies of thecollars 2l, and may have angular sockets 23 to receive the end of asmall wrench for tightening up the set screws.

In Figs. 1, 3, and 4, I illustrate the manner in which the wrench isapplied inside the projecting tube end or pipe section 24. This pipesection is illustrated as projecting from the face of the wall 25, andis also represented as provided with threads 26 which are located at itstip. In situations such as this, it is practically impossible to employan outside wrench without marring or injuring the face of the wall 25.If such a wrench is not applied substantially against the face of thewall 25, it will engage on the threads 26, and will crush them and attentheir peaks when the force is applied to the wrench to rotate the pipeend. My Wrench, however, engages inside vof the fitting, and cannotinjure the thread. And of course by reason of the fact that the wrenchis applied inside of the fitting, the face of the wall 25 will not besoiled or injured in any way.

In the present instance, I employ only two shackles l2, one at one sideof the jaws and the other at the other side Iof the jaws, and these twolinks will of course be located diametrically opposite to each other.

In practice, the peripheral faces 9 of the jaws should have a roughcharacter like that of a rasp or file, so that they will developsuiiicient resistance when they contact the inner face of the Wall ofthe fitting to develop enough drag on them to hold them stationary whilethe cam body 5 is rotated. As soon as this rotation takes place, thejaws will be expanded by the cam toes 4 that press against the adjacentfaces or edges of the jaws so that they will be pressed outward- 1y withconsiderable force.

In Fig. 4 the arrow indicates the direction of rotation as beinganti-clockwise, arid this of course would be the direction of rotationfor unscrewing a pipe tting that is connected to another tting by anordinary right-hand thread. This would ordinarily be the direction ofrotation. When it is necessary to return the pipe fitting to itsposition, or screw on a substitute pipe fitting, of course the directionof rotation would be clockwise in case the connection carries aright-hand thread.

By reason of the fact that the wrench is symmetrically formed, it isimmaterial whether the rotation is clockwise or anti-clockwise. Ineither case, the jaws will be expanded so as to jam them against thewall of the pipe fitting.

Many other embodiments of the invention may be resorted to withoutdeparting from the spirit of the invention.

I claim as my invention:

1. In a two-direction inside wrench for rotating a pipe-tting or thelike, the combination of a rotatable mandrel having cam means formed onthe body thereof, and having substantially cylindrical necks adjacentthe ends of said cam means, a pair of jaws having arcuate peripheriesand having recesses at their inner edges lying on opposite sides of themandrel at said cam means said jaws having sockets at opposite ends andon opposite sides, means loosely engaging said sockets for shacklingsaid jaws to each other, said shackling means permitting relative inwardmovement of said jaws and relative outward expanding movement withrespect to each other, washers mounted on the said necks of said mandrelfor retaining the shackling means in operative relation with said jawsand means adjustable on said mandrel for holding said washers inposition against said jaws; all of said parts cooperating so that whenthe mandrel is rotated in either direction, the cam means will expandthe jaws and jam them against the inner faces of the Wall of thefitting.

2. In an inside wrench for rotating a pipefitting or the like, thecombination of a rotatable mandrel, two jaws located on opposite sidesof said mandrel and adapted to be received within the pipe fitting, saidjaws having side faces with sockets disposed opposite each other, linkshaving lateral bent ends extending into said sockets, said socketsdisposed in pairs located on opposite sides of the axis of the mandrel,collars received over the mandrel and seating against the said linkswith means associated with the collars for securing them against thelinks; said mandrel including cam means for expanding the jaws to jamthem against the inner face of the fitting wall when the mandrel isrotated.

3. In a two-direction inside wrench, the combination of a mandrel havingcam means formed on the body thereof and provided with substantiallycylindrical necks at the ends of said cam means, a pair of jaws havingarcuate peripheries, and recesses at their inner edges lying on oppositesides of said mandrel at said cam means, means for shackling said jawsto each other including a pair of sockets on adjacent side faces of thejaws, and another pair of sockets on the adjacent side faces of the jawslocated diametrically opposite to the first named sockets, saidshackling means including links with bent ends loosely iitted in saidsockets, and means for retaining the shackling means in association withsaid jaws.

4. In a two-direction inside wrench for rotransversely to the axis ofthe mandrel, said jaws located adjacent the side faces of said mandreland adapted to be received within the pipefitting, shackles disposedrespectively at adjacent ends of the jaws for retaining the same on themandrel and operating to permit relative outward movement of said jawsaway from the mandrel; said mandrel having cam-means between said jawsoperating when the mandrel is rotated in either direction to expand thejaws and jam them against the wall of the tting; the side faces of saidjaws having sockets formed therein, said shackles including normallyinclined links with laterally extending ends received in said socketsand freely movable therein; and means mounted on the mandrel at theouter sides of said links for holding them in engagement with the jaws.

ROY R. GOSSARD.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 138,568 Littlejohn May 6, 187'3573,325 Gates Dec. 15, 1896 1,251,408 Murray Dec. 25, 1917 2,373,462Crow Apr. 12, 1945

